Some weapons are now wieldable with either one or two hands. Using two hands to wield a hybrid-grip weapon will always result in higher damage output than wielding it with one hand. Holding a weapon in one hand with the other hand free assumes you will wield the weapon with two hands if possible.

You can use the EXAMINE verb to see if a weapon is a hybrid-grip:

examine spearThe spear is mainly made of copper.It could be wielded in melee combat, its effectiveness dependent on your Polearms skill.The weapon feels of average balance, and you figure you could get up to 3 strikes per attack with it.It could be wielded with either one or two hands.It would allow you to keep a fair distance from opponents and dodge melee attacks more easily.The weapon would give you a slight advantage at parrying incoming blows.After hefting the spear a few times, you figure it weighs 5 pounds.Roundtime: 5 seconds.

Many hafted and polearm weapons are hybrid-grip, as well as some swords and chained weapons.